At present there is a well-recognized need for regular physical exercise for its cardiovascular benefits, to overcome weight problems and to improve muscle tone. It is often the case that persons who exercise regularly and do not have weight problems, as a habit, will lapse into poor posture that makes it appear they are overweight. The problem has been recognized as lack of proper control over the abdominal muscles. To confront this problem various abdominal muscle expansion warning devices have been developed. They are typically worn as a belt around the waist, and when the user's stomach muscles expand against the belt line to a preset maximum, thereby indicating poor posture, the warning device sounds or otherwise warns the user that he has allowed the abdominal muscles to relax beyond the desired limit. The user can then tighten the abdominal muscles and immediately regain proper posture. Such warning devices can have the advantage of retraining the stomach muscles if the warning devices are used constantly, so that everyday use can ultimately produce good posture as the norm. Good posture also can have the benefit of alleviating chronic back problems or other undesired physical symptoms of poor posture.
The present invention is based on a recognition that prior posture monitoring and warning devices which are worn as a belt are not useful as a practical matter in being wearable constantly throughout the day, particularly in social situations, such that the user would want to constantly wear the belt on an ongoing basis.
Most prior belt-type devices having posture warning systems contain variations of electronic circuits to produce audible sounds such as a buzzer or an alarm. Most electronic devices produce a continuous audible sound. Other warning devices either generate a light signal as an alternative, or others use a mechanical vibrating action to warn the user of poor posture.
There is a need for an abdominal expansion monitoring and warning device that is capable of sensing and warning the user about abdominal muscle expansion beyond a preset limit, without the use of electronic monitoring or warning devices which generate a loud or continuous audible alarm sound. This can be annoying in public and would otherwise discourage the user from wearing the belt continuously from day to day. Such electronic devices also are unduly complicated and costly to manufacture. There is also a need for such a monitoring/warning device which is not readily noticeable when being worn and may be easily worn under the clothing separate and apart from a normal belt for trousers or the like. Further, there is a need for a posture warning device that does not add an uncomfortable amount of weight, can easily be used to set the expansion limit, and is reliable in its operation.